Disc brakes and wheel changes/pad alignment

[wheelsONfire]

Some say, when you pull the wheel off your disc brake bike, there could be an issue to get the pads and rotors to fit proper!?

Why would this be? Do brake pads shut/ close when wheel comes out?

Do you need to re-align the brake pads,... or?

Is this related to QR releases only, or does it also happen if you use through-axle (15*100/12*142)?

How do you do it, not to get this delicate problem?

I don't see how it could have anything to do with 6-bolt hubs compared to centerlock, or ?

Asking to learn/ understand, so bare level with me

Bike will use:

* Rotor RT86 6-hole
* BR-R785
* 6-hole hub

[mattr]

Disc spacing from the dropout and disc thickness are the two main issues. They can vary by model/manufacturer.

Pulling the lever when there is no wheel in is the other.

[Tamu8104]

This really comes down to manufacturing tolerances on the wheels and rotors that may result in some slight variation while the clearances are extremely tight in the calipers.

QR is more susceptible to this than TA but you can still get it with TA. All in all, not that hard to deal with, loosen the caliper bolts slightly once the new wheel is in, grab and hold the brake lever and tighten the bolts. Takes a minute or two and you should be good to go.

[Birdman]

@wheelsONfire, If I understand you correctly, you are asking about the same wheel set coming off (for travel or some other reason) and rotor/pad misalignment could occur when reinstalling the same set of wheels on the same bike?

This is never an issue for me on my QR equipped Fuji Altamira CX disc. It is only NOT an issue for me because i take my time on installing my wheels. I always make sure the hubs are fully seated at the base of the drop out, so I always get consistent rotor/pad alignment between wheel installations. The root cause is really the axle-to-drop out alignment consistency. The key is to install the calipers with the hubs well seated in the drop out.

I can see this being an annoyance in race situation where quick wheel swap is critical, but none issue for a recreational rider like me where I take a few extra seconds on wheel installation.

Through axle takes all these axle-to-drop out alignment consistency issue out of the way.

[wheelsONfire]

Yes like if you change tire, tube or such. Thinking of it, it's really close to same with QR and rim brake wheels. But it's perhaps easier to re-align rim brakes and / or wheels? I looked at a clip from Syntace and they just pull out the wheel and insert it again and it seems to work spot on.
But on the other hand, it's a video clip and how do i know how if there became some rub or not....

[thp]

I've had slightly different alignments going from wheels with 6-bolt and centerlock. Other than that, you should have zero issues swapping the same wheels with QR. Just remember to put some weight the bike when clamping the QR to make sure the hub is fully inserted. Also not # of turns for pads too if they interfere between different wheels. Just like swapping wheels with different hubs on a road bike, fun adjusting the limit screws.

[spookyload]

If you have two sets of wheels that are different, you can use thin spacers between the rotor and the hub to shim the rotor so it shifts it over to align with the other wheel. They make insanely thin round shims for shimming rotors/calipers.

[gtinut]

If you have two sets of wheels that are different, you can use thin spacers between the rotor and the hub to shim the rotor so it shifts it over to align with the other wheel. They make insanely thin round shims for shimming rotors/calipers.

this is the way to do it. Not many people know about these shims.

[Calnago]

Wonder if mechanics in the pro peloton will be running around with a bunch of these shims in their pockets for "super fast" neutral wheel changes